Solar panels produce direct current (DC) which must be converted to alternating current (AC). Typically, useable outputs from solar panel installations are 240 volts AC at 60 Hz for North American installations. In some photovoltaic solar panel installations a single inverter may convert the DC outputs to AC from a string of solar panels.
Using a single inverter for a string of solar panels has some disadvantages. DC cables and attendant diodes are necessary to connect individual solar panels with the inverter. This adds a level of cost, complexity and associated installation labor. There are also inherent dangers. DC strings from solar panels can exceed 600 volts, which cannot be readily shut off.
An alternative approach is to use a single micro-inverter with each solar panel. As the name implies, micro-inverters are small inverters intended to handle the output of a single solar panel. Most are rated at about 260 watts. This enables one to isolate and tune the output of a solar panel. Large transformers for reducing cooling loads aren't needed nor are cooling fans. There is also evidence that overall efficiencies of solar installations are higher with the use of micro-inverters with each solar panel.
With micro-inverters, any solar panel that is under-performing will not have an adverse effect on the panels around it. Micro-inverters produce grid matching power directly at the back of a solar panel. Arrays of solar panels are connected in parallel to each other and then to the grid feed. Thus, a single failing panel or inverter will not take the entire solar panel string offline.
Although there are obvious advantages in employing micro-converters for the conversion of DC to AC emanating from solar panels, such products have experienced issues limiting their longevity. Specifically, it has been found that the high temperatures associated with the photovoltaic panels have resulted in micro-inverter failures. This situation has been somewhat addressed by component selection and the employment of UV glass surface treatment on the panels themselves which reduces heat buildup.
Other problems also exist. Since the solar panels create a warm environment animals such as rodents tend to migrate to these areas. In turn, they can chew or damage solar panel wire conductors. Theft of micro-inverters is also a problem. Finally, replacement of micro-inverters is often difficult and labor intensive.
It is therefore an object of the invention to provide an improved solar panel array utilizing a single micro-inverter for each solar panel.
Another object of the invention is to provide an improved mounting arrangement of a micro-inverter to a solar panel.
Another object of the invention is to mount a micro-inverter so as to be in direct contact with the outputs of a solar panel to thereby eliminate micro-inverter wire leads and diodes.
Still another object of the invention is to provide a system and method of mounting micro-inverters directly to solar panels in a manner that provides easy installation.
Yet another object of the invention is to provide a system whereby micro-inverters that are underperforming or not performing are easily replaced from a solar panel.
Another object of the invention is to mount a micro-inverter to a solar panel to minimize exposure of heat created by the solar panel.
Another object of the invention is to provide a method and structure to easily connect and disconnect the micro-inverter output cable to an AC trunk cable connected to a plurality of micro-inverters.
These and further objects will be readily apparent when considering the following disclosure and appended claims.